Voice and video in libPurple is being worked on using Farstream (formerly Farsight). There are a few parts to this implementation. Firstly, basic API support needs to be added to libPurple. Then Pidgin and Finch need to be able to initiate, participate in, and terminate the voice and video sessions. After these two requirements are met, each protocol will require both the signaling to be implemented (such as SIP or Jingle) and the proper Farstream plugins.
Farstream has rawudp, iceudp, and multicast transmitter plugins and an MSN webcam plugin. Basic voice and video support for libPurple, Pidgin, and Finch (voice support only) have been added to the “default” development branch. XMPP/GTalk/Gmail is working, but not complete. None of the other protocols have had much work done.
XMPP, GTalk, and Gmail use RTP. XMPP uses Jingle. GTalk and Gmail use their own flavor of Jingle. XMPP uses rawudp and XMPP, GTalk, and Gmail use the libnice Farstream transmitter plugin.
Voice and video support for XMPP/GTalk was worked on for a Summer of Code project in the year 2008.
Sametime seems to support at least voice chat according to this IBM document
This is a placeholder for information regarding GG voice.
An announcement that might be of interest
Please be familiar with compiling and installing code from source. Please also submit any bugs you find to our issue tracking platform, checkout our Contributing page for more details.
Make sure you are using the latest release of Pidgin.
Farsight 2 0.0.9 and libNice 0.0.7 are the minimum versions required, but the newest versions you can get are best. Make sure to check Farsight2’s README and make sure you have all of the dependencies for it. gst-plugins-base is also required for the gstreamer-interfaces-0.10 interface. Some distros call it libgstreamer-plugins-base0.10-dev. If everything in order, the configure script should output this line:
Build with voice and video…. yes
For help with building, see Building Pidgin. Please carefully read through that section and any extra information for the distribution you’re using.
If a certain codec isn’t working for you, you need to create an “fs-codec.conf” file in your purple config directory. See this for the specification: fs-codec-list-from-keyfile
So, for example, if you want to disable the MPV codec you’d put this in the fs-codec.conf file: